Imaging apparatus and method for controlling the imaging apparatus

ABSTRACT

An imaging apparatus includes an image generation unit configured to photoelectrically convert an object image formed by an imaging optical system to generate an image, a control unit configured to perform focusing control of the imaging optical system, an object detecting unit configured to detect a plurality of object regions based on the image generated by the image generation unit, and a display unit configured to display the plurality of object regions detected by the object detecting unit. The object detecting unit sequentially detects the object regions at a plurality of positions to which the imaging optical system is moved, and the display unit juxtaposes and displays the object regions detected by the object detecting unit with respect to the image.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.12/407,254, filed Mar. 19, 2009, which claims priority from JapanesePatent Application No. 2008-088754 filed Mar. 28, 2008, which are herebyincorporated by reference herein in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an imaging apparatus and a method forcontrolling the imaging apparatus. More particularly, the presentinvention relates to an imaging apparatus that detects a face of anobject using an image signal output from an image sensor when a personis shot as the object, and also relates to a method of controlling theimaging apparatus.

2. Description of the Related Art

Conventionally, an autofocus (AF) camera of the phase-differencedetection type having a plurality of focus detection points peformsfocal position detection at each of the plurality of focus detectionpoints in a field. Then, the AF camera performs control to focus on afocus detection point that is automatically or intentionally selectedfrom among the focus detection points. In the automatic focus detectionpoint selection, a general camera selects and focuses on a focusdetection point having the shortest distance to an object based on thefocus detection results at the focus detection points.

Furthermore, there are AF cameras of the contrast type, which capturesan object image formed by an imaging lens using an image sensor anddetermines an in-focus position using an image signal obtained from afocus area. The camera of the contrast type performs focusing on a focalposition having a peak focus evaluation value in the focus area.

In AF cameras of the contrast type, a camera that detects a region of aface of a person and focuses on the face is known. Regarding the facedetection method, Japanese Patent Application Laid-Open No. 8-63597discusses a method for determining a face candidate region correspondingto the shape of a face of a person and determining a face region basedon feature information of the face candidate region. Further, JapanesePatent Application Laid-Open No. 8-63597 discusses a method fordetecting a face candidate region by extracting an outline of a face ofa person from an image and a method for calculating a correlation valuebetween a plurality of templates of various shapes of faces anddetecting a face candidate region based on the correlation value.

However, in the above-described AF focus detection methods, it isdifficult to perform focusing under a condition where the depth of fieldbecomes shallow with a camera to which a lens having a long focal lengthis mounted. For example, when a plurality of persons exist at differentdistances, a main object, on which a photographer intends to focus, doesnot always exist within the depth of field. In such a case, it isdifficult to focus on the main object.

In a camera of the phase-difference detection type, when control isautomatically performed to focus on a focus detection point from among aplurality of focus detection points, if an unexpected object exists nearthe focus detection point, the unexpected object may be focused.Accordingly, in the camera of the phase-difference detection type, it isdifficult to focus on a main object a photographer intends to shoot.

Moreover, in the camera of the contrast type, focusing is performed suchthat an object having a maximum peak contrast is to be focused.Accordingly, for example, when a peak of the contrast of a background islarger than that of a main object, the background may be focused.Further, for example, when a peak of the contrast of clothes is largerthan that of the face of the object, the clothes may be focused. Asdescribed above, in a camera of the contrast type, the position of focusto be detected is unstable, and it is difficult to focus on a point aphotographer intends to focus.

In a camera of the face detection type that detects a face of an objectand focus on the face, it is possible to detect a face of an objectexisting within the depth of field. However, if a main object does notexist within the depth of field, it is difficult to find the mainobject.

To solve the drawbacks described above, Japanese Patent ApplicationLaid-Open No. 2006-345254 discusses a method for detecting faces of aplurality of objects and grouping the faces based on shootingparameters, such as object distances and object luminance values of thefaces. In the method discussed in Japanese Patent Application Laid-OpenNo. 2006-345254, by setting optimum shooting parameters for each group,it is possible to perform shooting with the optimum shooting parametersfor each object.

However, under a condition where the depth of field of a camera isshallow, if a plurality of persons exist at different distances, it isdifficult to focus on a main object a photographer intends to focus.

When a main object does not exist within the depth of field at thecurrent focal position, it is necessary to focus on the main objectwithin the depth of field at another focal position by driving afocusing lens. In such a case, if a camera of the phase-differencedetection type is used, a closest object is focused. If a camera of thecontrast type is used, a point having the highest peak of contrast isfocused. However, in both cases, the focused points are not always amain object.

There is a method for detecting faces of a plurality of objects,grouping the faces based on shooting parameters, such as objectdistances and object luminance values of the faces, setting shootingparameters optimum for each group, and performing shooting. In themethod, with a single release operation, shooting is performed at aplurality of focal points where the faces of the objects are detected.Accordingly, it is possible to perform shooting on a plurality ofpersons within an image plane.

In the method described above, an image of the well focused main objectcan be recorded. However, it is necessary to record the other images.Accordingly, unnecessary images are recorded, and it takes a lot of timeto organize the shot images. Further, in this method, when a pluralityof persons exist within an image plane, it is not possible to record animage with only a main object focused.

SUMMARY OF THE INVENTION

The present invention is directed to an imaging apparatus that detects,for example, faces of objects, and focuses on the objects, and displaysthe objects of which detection of object regions are established as alist. Further, the present invention is directed to an imaging apparatusthat can select an object to focus on as a main object and focus on theselected object.

According to an aspect of the present invention, an imaging apparatusincludes an image generation unit configured to photoelectricallyconvert an object image formed by an imaging optical system to generatean image, a control unit configured to perform focusing control of theimaging optical system, an object detecting unit configured to detect aplurality of object regions based on the image generated by the imagegeneration unit, and a display unit configured to display the pluralityof object regions detected by the object detecting unit. The objectdetecting unit sequentially detects the object regions at a plurality ofpositions to which the imaging optical system is moved, and the displayunit juxtaposes and displays the object regions detected by the objectdetecting unit with respect to the image.

Further features and aspects of the present invention will becomeapparent from the following detailed description of exemplaryembodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate exemplary embodiments, features,and aspects of the invention and, together with the description, serveto explain the principles of the invention.

FIG. 1 is a block diagram illustrating a camera according to anexemplary embodiment of the present invention.

FIG. 2 is a flowchart illustrating imaging processing performed by thecamera according to an exemplary embodiment of the present invention.

FIG. 3 is a flowchart illustrating face search processing according toan exemplary embodiment of the present invention.

FIG. 4 is a flowchart illustrating face list displaying processingaccording to an exemplary embodiment of the present invention.

FIG. 5 illustrates a first display format of a face list in a displaydevice according to an exemplary embodiment of the present invention.

FIG. 6 illustrates a second display format of the face list in thedisplay device according to an exemplary embodiment of the presentinvention.

FIG. 7 illustrates a third display format of the face list in thedisplay device according to an exemplary embodiment of the presentinvention.

FIG. 8 illustrates a fourth display format of the face list in thedisplay device according to an exemplary embodiment of the presentinvention.

FIG. 9 illustrates a fifth display format of the face list in thedisplay device according to an exemplary embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Various exemplary embodiments, features, and aspects of the inventionwill be described in detail below with reference to the drawings.

FIG. 1 is a block diagram illustrating a camera (imaging apparatus) 100according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the camera 100 includes an imaging optical system(imaging lens) 101 and an image sensor 107 having a plurality of pixels.The image sensor 107 includes a charge-coupled device (CCD), acomplementary metal-oxide semiconductor (CMOS) sensor, or the like, onwhich an optical image of an object is formed by the imaging opticalsystem 101. The image sensor 107 photoelectrically converts the objectimage formed by the imaging optical system 101 and outputs an imagesignal.

A main mirror 102, which has a semi-transmissive section, moves to theoutside of an imaging light flux during shooting, and is obliquelydisposed in the imaging light flux (on an optical path) during focusdetection. FIG. 1 illustrates a state (mirror down) in which the mainmirror 102 is inserted into the imaging light flux. In a state in whichthe main mirror 102 is obliquely disposed in the imaging light flux, themain mirror 102 guides a part of light flux that is transmitted throughthe imaging optical system 101 to a finder optical system, whichincludes a focusing screen 103, a pentagonal prism 104, and an eyepiecelens 105.

A sub mirror 106 can be folded or extended relative to the main mirror102 in synchronization with operation of the main mirror 102. A part ofthe light flux transmitted through the semi-transmissive section of themain mirror 102 is reflected downward by the sub mirror 106 and enters afocus detection device 108 of the phase-difference type. Thus, afocusing state of the imaging optical system 101 can be detected.

In cameras of the contrast type, the main mirror 102 is always moved tothe outside of the imaging light flux. In synchronization with theoperation, in a state in which the sub mirror 106 is folded relative tothe main mirror 102 (mirror up), an object optical image transmittedthrough the imaging optical system 101 is formed on the image sensor107. Thus, a focusing state of the imaging optical system 101 can bedetected.

An analog signal processing circuit 109 performs processing, such asdenoising processing, on an image signal output from the image sensor107 based on the light quantity of an object optical image formed by theimaging optical system 101. An analog-to-digital (A/D) converter 110converts the analog signal output from the analog signal processingcircuit 109 into a digital signal.

A digital signal processing circuit 111, which is connected to a systemcontroller 112 (described below), performs image processing, such asshading correction or gamma correction, on the digital signal outputfrom the A/D converter 110.

The above-described image sensor 107, the analog signal processingcircuit 109, the A/D converter 110, and the digital signal processingcircuit 111 constitute an image generation unit 130. The imagegeneration unit 130 photoelectrically converts an object image formed bythe imaging optical system 101 to generate an image.

The system controller 112 includes a central processing unit (CPU) forperforming overall control of the camera 100, and a storage device(storage unit), such as a random access memory (RAM). The systemcontroller 112 appropriately controls operation of various parts, suchas a lens driving device 113 (described below). The storage device inthe system controller 112, as will be described below, stores focalpositions and image locations of a plurality of object regions detectedby a an object detection unit, such as a face detection circuit 121.

The lens driving device (lens driving unit) 113 is connected to thesystem controller 112. The lens driving device 113 includes acommunication circuit that communicates with the imaging optical system101, a lens driving mechanism that drives the imaging optical system 101to adjust focus, and a driving circuit that drives the drivingmechanism.

The system controller 112 and the lens driving device 113 constitute acontrol unit 140. As will be described below, the control unit 140performs focusing control of the imaging optical system 101.

A mirror driving device 114, which is connected to the system controller112, drives the main mirror 102 to the outside of the imaging lightflux. An image sensor driving device 115, which is connected to thesystem controller 112, drives the image sensor 107.

A buffer memory 116, which is connected to the digital signal processingcircuit 111, functions as a frame memory that can store data of aplurality of frames captured by the image sensor 107. A digital signaloutput from the A/D converter 110 is temporarily stored in the buffermemory 116. The digital signal processing circuit 111 reads the datastored in the buffer memory 116, and performs the above-describedprocessing. The data processed by the digital signal processing circuit111 is stored in the buffer memory 116.

A recording/reproducing signal processing circuit 117 is connected tothe digital signal processing circuit 111. As described above, the imagedata on which various digital processing is performed in the digitalsignal processing circuit 111 is stored in the buffer memory 116. Therecording/reproducing signal processing circuit 117, after theprocessing, records the image data stored in the buffer memory 116 on anexternal storage medium 118, such as a memory card.

In recording the image data on the external storage medium 118, imagedata compression is performed, for example, in accordance with JointPhotographic Experts Group (JPEG) format. In reading the image data fromthe external storage medium 118, the recording/reproducing signalprocessing circuit 117 performs decompression processing on the imagedata. The recording/reproducing signal processing circuit 117 includesan interface for performing data communication between therecording/reproducing signal processing circuit 117 and the externalstorage medium 118.

A display device (display unit) 120 displays an image captured by theimage sensor 107. The display device 120 is also used to reproduce anddisplay the image data recorded on the external storage medium 118. Todisplay an image on the display device 120, the image data stored in thebuffer memory 116 is read. The read image data is converted from digitalimage data into an analog video signal by a digital-to-analog converter(D/A converter) 119. The display device 120 displays the image using theanalog video signal converted by the D/A converter 119. As will bedescribed below, the display device 120 displays a plurality of objectregions detected by the face detection circuit 121.

In displaying an image captured by the image sensor 107 on the displaydevice 120, two types of display formats are provided. One format is adisplay format used when a release operation is not performed. Thedisplay format is referred to as a through-image. In the display format,an image repeatedly captured by the image sensor 107 is sequentiallyupdated and displayed. The other format is referred to as a freezeimage. In the freeze image format, after a release operation of thecamera 100 is performed, an image captured by the image sensor 107 isdisplayed for a predetermined period of time.

The face detection circuit (object detection unit) 121 is connected tothe digital signal processing circuit 111. The face detection circuit121 detects whether a face (object region) is contained in the imagedata on which various digital processing is performed by the digitalsignal processing circuit 111. As described above, based on the imagegenerated by the image generation unit 130, the face detection circuit121 detects a plurality of object regions. Regarding the face detectionmethod, for example, Japanese Patent Application Laid-Open No. 8-63597discusses it.

An operation unit (instruction unit) 122 is connected to the systemcontroller 112. The operation unit 122 includes operation members usedto operate the camera 100. The operation members include a power supplyswitch for turning on or off a power source of the camera 100, a releasebutton, and a setting button for selecting a shooting mode, such as aperson shooting mode. By operating the switches or buttons, a signalcorresponding to the operation is input to the system controller 112. Aswill be described below, the operation unit 122 is used to select one ofa plurality of object regions displayed on the display device 120. Then,the system controller 112 performs focusing control on the object regionselected by the operation unit 122.

A release switch SW1, which is operable by the photographer to be turnedon by a first stroke operation (half press operation) of the releasebutton, and a release switch SW2, which is operable by the photographerto be turned on by a second stroke operation (full press operation) ofthe release button are connected to the release button.

Next, imaging processing performed by the camera 100 according to anexemplary embodiment of the present invention is described.

FIG. 2 is a flowchart illustrating imaging processing performed by thecamera according to an exemplary embodiment of the present invention. Inthe imaging processing according to the exemplary embodiment of thepresent invention, shooting is performed by detecting and recognizingfaces of objects and focusing on a face of a main object.

In step S101, the system controller 112 determines whether the releaseswitch SW1, which is apart of the operation unit 122, is pressed. If therelease switch SW1 is not pressed (NO in step S101), the processing instep S101 is repeated until the release switch SW1 is pressed. On theother hand, if the release switch SW1 is pressed (YES in step S101), theprocessing proceeds to step S102.

In step S102, the system controller 112 communicates with the imagingoptical system 101 via the lens driving device 113, and drives theimaging optical system 101 within an entire drive range of the imagingoptical system 101. With such control, the face detection circuit 121can detect, in a plurality of focal positions, faces of objects in theimage data on which various processing is performed by the digitalsignal processing circuit 111. The face search processing is describedbelow.

Step S102 includes an image generation step for photoelectricallyconverting an object image formed by the imaging optical system 101 togenerate an image, and a detection step for detecting a plurality ofobject regions based on the image generated in the image generationstep.

In step S103, the system controller 112 determines whether facedetection is established as a result of the face search processing instep S102. If the face detection is not established (NO in step S103),the imaging processing ends. On the other hand, if the face detection isestablished (YES in step S103), the processing proceeds to step S104.

In step S104, the system controller 112 generates a list of a pluralityof faces of which the detection is established in step S102. Thegenerated list of faces is displayed on the display device 120 via thedigital signal processing circuit 111. As described above, step S104includes a displaying step for displaying a plurality of object regionsdetected in step S102. The displaying step will be described in detailbelow.

In step S105, the system controller 112 determines whether a face onwhich the photographer intends to focus as a main object is selectedfrom the list of faces displayed on the display device 120 in step S104using the operation unit 122. The determination is performed by thesystem controller 112. If the selection of a face by the photographer isnot performed (NO in step S105), the processing returns to step S101,and the above processing is repeated. On the other hand, if the intendedface is selected by the photographer (YES in step S105), the processingproceeds to step S106.

In step S106, the system controller 112 drives the imaging opticalsystem 101 via the lens driving device 113 to the focal position wherethe detection of the face selected in step S105 is established. Asdescribed above, step S106 includes a control step for performingfocusing control on the selected object region by, in step S105,selecting one of a plurality of object regions displayed in step S104.

In step S106, the lens driving device 113 drives the imaging opticalsystem 101 to the focal position of the object region selected using theoperation unit 122. The operation is performed by the system controller112 reading the focal position of the object region selected using theoperation unit 122 from the storage device (storage unit) in the systemcontroller 112, as described in further detail below. The lens drivingdevice 113 (control unit 140) performs focusing control based on thefocal position of the object region read from the storage device.

After the control, the face detection processing can be performed onceagain, or the processing can directly proceed to step S107.

In step S107, the system controller 112 determines whether the releaseswitch SW2, which is a part of the operation unit 122, is pressed. Ifthe release switch SW2 is not pressed (NO in step S107), the processingreturns to step S101, and the above processing is repeated. On the otherhand, if the release switch SW2 is pressed (YES in step S107), theprocessing proceeds to step S108.

In step S108, the system controller 112 performs shooting and stores theshot image.

Next, the face search processing performed in step S102 in FIG. 2 isdescribed in detail. FIG. 3 is a flowchart illustrating the face searchprocessing performed in step S102.

In step S201, the system controller 112 determines whether the facesearch processing is performed within the entire drive range of themounted imaging optical system 101 via the lens driving device 113. Ifthe face search processing is performed within the entire drive range ofthe imaging optical system 101 (YES in step S201), the face searchprocessing ends. On the other hand, if the face search processing is notperformed within the entire drive range of the imaging optical system101 (NO in step S201), the processing proceeds to step S202.

In step S202, the system controller 112 writes an image signal outputfrom the image sensor 107 as image data into the buffer memory 116 viathe A/D converter 110 and the digital signal processing circuit 111.

In step S203, based on the image data written into the buffer memory 116in step S202, the face detection circuit 121 performs the face searchprocessing (face recognition processing).

In step S204, the system controller 112 determines whether the facerecognition processing is established in step S203. If the facerecognition processing is not established (NO in step S204), theprocessing proceeds to step S206. On the other hand, if the facerecognition processing is established (YES in step S204), the processingproceeds to step S205.

In step S205, the system controller 112 stores the faces, the focalpositions, and the image locations at the time of establishment of theface recognition processing in step S203 into the storage device in thesystem controller 112. As described above, the system controller 112stores the focal positions and image locations of a plurality of objectregions detected by the face detection circuit 121.

In step S206, the system controller 112 performs focal positionadjustment via the lens driving device 113, which drives the imagingoptical system 101. After the focal position adjustment is completed,the processing returns to step S201. Then, the processing from step S201to step S206 is repeated until the face search processing within theentire drive range of the imaging optical system 101 is completed.

Next, the face list displaying processing performed in step S104 in FIG.2 is described in detail. FIG. 4 is a flowchart illustrating the facelist displaying processing performed in step S104.

In step S301, the system controller 112 determines whether the facerecognition is established in the face search processing in the stepS102. If the face recognition is not established (NO in step S301), theprocessing proceeds to step S304. In step S304, the system controller112 notifies the photographer that the face recognition is notestablished. On the other hand, if the face recognition is established(YES in step S301), the processing proceeds to step S302.

In step S302, the digital signal processing circuit 111 in the imagegeneration unit 130 sorts the faces recognized in step S301. The sortingcan be performed, for example, in order of distance, or in order ofimage location. In performing the sorting of the faces, informationabout the focal positions or the image locations of a plurality of facesdetected by the face detection circuit 121 is read from the storagedevice provided in the system controller 112 in the control unit 140.Based on the information, the digital signal processing circuit 111performs the sorting processing.

When the sorting processing is performed according to the distanceorder, for example, the faces can be juxtaposed from the nearest face tothe farthest face. When the sorting processing is performed according tothe order of image location, for example, the faces can be juxtaposed inthe direction from a central part to a peripheral part of the imageplane, in the direction from the left to the right of the image plane,or in the clockwise direction. The faces can also be juxtaposed with acombination of the above-described directions. Further, the faces can bedisplayed without sorting the faces, for example, in order of theestablished face detection or at random.

In step S303, the system controller 112 displays the list of the facesgenerated in step S302 on the display device 120. More specifically, theimage generation unit 130 instructs the display device 120 to displaythe plurality of object regions based on the information about theplurality of object regions detected by the face detection circuit 121.Examples of the display are illustrated in FIGS. 5 to 7. FIGS. 5 to 7illustrate display formats of the face list on the display device 120according to an exemplary embodiment of the present invention.

As illustrated in FIG. 5, as a display format of the face list, a firstdisplay format that displays an image 201 in live view and a face list202 can be employed. In the display format, corresponding to objects Ato H in the image 201 in live view, faces a to h of the objects aredisplayed, respectively.

In the first display format of the face list in FIG. 5, the face list202 (faces a to h) is sorted in distance order in step S302. Then, thefaces are juxtaposed from the object A that exists at a short distanceto the object H that exists at a far distance, and in the order left toright. The faces displayed in the face list 202 can be displayed at theoriginal size of the object region stored in the storage device in thesystem controller 112 in the face search processing, or can be displayedby enlarging or reducing to a predetermined size.

The image 201 in live view is displayed by focusing on the object A thatis the nearest object in the face list 202. The image 201 in live viewcan be focused on the nearest object A until the photographer displaysthe face list 202 and selects a face to focus. Alternatively, an imagethat is focused in the order from the object A to the object H for everypredetermined period of time can be displayed.

As a display format of the face list, as illustrated in FIG. 6, a seconddisplay format that displays only an object face list (faces a to h) 203can be employed. Further, as illustrated in FIG. 7, a third displayformat that displays an image 204 by combining an image in live viewwith faces on which face detection is established can be employed. Alsoin the third display format, corresponding to the objects A to H, thefaces a to h are displayed, respectively. The display formats of theface list can be changed by the photographer operating the operationunit 122.

FIG. 8 illustrates a fourth display format of the face list on thedisplay device 120 according to an exemplary embodiment of the presentinvention. FIG. 8 illustrates a scene in which objects I, J, and K existat the same distance from the camera. It is assumed that the objects I,J, and K exist within the depth of field at the same focal position.

In an image 301 in live view, an image of the objects I, J, and K thatare in an in-focus state is displayed. In a face list 302, faces i, j,and k of the objects I, J, and K, respectively, of which face detectionis established are displayed in the order of image location(counterclockwise from a central part to a peripheral part of the imageplane).

FIG. 9 illustrates a fifth display format of the face list on thedisplay device 120 according to an exemplary embodiment of the presentinvention. Similar to FIG. 8, FIG. 9 illustrates a scene in whichobjects I, J, and K exist at the same distance from the camera.

If the objects I, J, and K exist within the depth of field at the samefocal position, the objects I, J, and K can be grouped as an object Lsuch that the image is displayed as an image 401 in live view in FIG. 9.In a face list 402, a face 1 that is a representative of the group L canbe displayed. In the processing, as the face 1, for example, a face atthe center of the image plane is selected in the order of imagelocation. The grouping can be performed by operating the operation unit122 by the photographer or can be automatically performed based on thenumber of objects in the image plane. As described above, when the facedetection circuit 121 detects a plurality of object regions within thedepth of field, the system controller 112 (image generation unit 130)groups the plurality of object regions and displays the representativeobject region on the display device 120.

As described above, in an imaging apparatus according to an exemplaryembodiment of the present invention, by selecting a face of an object aphotographer intends to focus as a main object from a displayed list offaces of which the face detection is established, focusing control canbe performed on the main object. Accordingly, the imaging apparatus canperform focusing control on a main object selected by a photographer.

In the above descriptions, the object the photographer intends to focusis described as a person, and the region for the focal positionadjustment is described as the region of which the face detection isperformed. However, an exemplary embodiment of the present invention isnot limited to the above. For example, an object image can be clippedfrom a background to perform object detection. Then, a regioncorresponding to the object position can be set as an object region forfocal position detection.

While the present invention has been described with reference to theexemplary embodiment, it is to be understood that the invention is notlimited to the disclosed exemplary embodiment. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all modifications, equivalent structures, and functions.

1. An imaging apparatus comprising: an image generation unit configuredto photoelectrically convert an object image formed by an imagingoptical system to generate an image; a control unit configured toperform focusing control of the imaging optical system; an objectdetecting unit configured to detect a plurality of object regions basedon the image generated by the image generation unit; a display unitconfigured to display a plurality of object region images representingthe plurality of object regions detected by the object detecting unit,wherein the plurality of object region images differ from the image; anda selection unit configured to select an object region image from amongthe plurality of object region images, wherein the object detecting unitdetects the object regions at a plurality of positions to which theimaging optical system is moved, and wherein the control unit performsfocusing control based on selection result of the selection unit.
 2. Theimaging apparatus according to claim 1, wherein the display unitdisplays the plurality of object region images with respect to theimage.
 3. The imaging apparatus according to claim 1, wherein thedisplay unit juxtaposes and displays the plurality of object regionimages with respect to the image.
 4. The imaging apparatus according toclaim 1, wherein the display unit juxtaposes and displays the pluralityof object region images based on focal positions corresponding to theobject regions.
 5. The imaging apparatus according to claim 1, whereinthe display unit juxtaposes and displays the plurality of object regionimages based on positions of the object regions in an image plane. 6.The imaging apparatus according to claim 1, wherein the display unitjuxtaposes and displays the plurality of object region images based on adistance order of the object regions.
 7. The imaging apparatus accordingto claim 1, wherein the selection unit selects an object region imagebased on user's instruction.
 8. A method for controlling an imagingapparatus, the method comprising: photoelectrically converting an objectimage formed by an imaging optical system to generate an image;performing focusing control of the imaging optical system; detecting aplurality of object regions based on the generated image; displaying aplurality of object region images representing the detected plurality ofobject regions, wherein the plurality of object region images differsfrom the image; selecting an object region image from among theplurality of object region images, detecting the object regions at aplurality of positions to which the imaging optical system is moved; andperforming focusing control based on result of selecting.